text: /* mbed Microcontroller Library
   * Copyright (c) 2017-2017 ARM Limited
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  #ifndef BLE_PAL_GAP_H_
  #define BLE_PAL_GAP_H_
  
  #include "platform/Callback.h"
  #include "ble/pal/GapTypes.h"
  #include "GapEvents.h"
  #include "blecommon.h"
  
  namespace ble {
  namespace pal {
  
  /**
   * Adaptation interface for the GAP layer.
   *
   * Define the primitive necessary to realize GAP operations. the API and event
   * follow closely the definition of the HCI commands and events used
   * by that layer.
   */
  struct Gap {
      struct EventHandler {
          /**
           * @copydoc Gap::EventHandler::onReadPhy
           */
          virtual void on_read_phy(
              pal::hci_error_code_t status,
              connection_handle_t connectionHandle,
              ble::phy_t tx_phy,
              ble::phy_t rx_phy
          ) = 0;
  
          /**
           * @copydoc Gap::EventHandler::onDataLengthChange
           */
          virtual void on_data_length_change(
              connection_handle_t connection_handle,
              uint16_t tx_size,
              uint16_t rx_size
          ) = 0;
  
          /**
           * @copydoc Gap::EventHandler::onPhyUpdateComplete
           */
          virtual void on_phy_update_complete(
              pal::hci_error_code_t status,
              connection_handle_t connection_handle,
              ble::phy_t tx_phy,
              ble::phy_t rx_phy
          ) = 0;
  
          /**
           * Should be invoked by the Gap implementation when an enhanced
           * connection complete event happens.
           *
           * @param status hci_error_code::SUCCESS in case of success or an error
           * code.
           *
           * @param connection_handle The handle of the connection created.
           *
           * @param own_role Indicate if the local device operates as slave or
           * master.
           *
           * @param peer_address_type Type of address of the peer.
           *
           * @param peer_address Address of the peer connected.
           *
           * @param local_resolvable_private_address Resolvable private address
           * being used by the controller. If not applicable, the address is full
           * of zeroes.
           *
           * @param peer_resolvable_private_address Resolvable private address
           * being used by the peer. If not applicable, the address is full of
           * zeroes.
           *
           * @param connection_interval Interval between two connection events.
           * Unit is 1.25ms.
           *
           * @param connection_latency Slave latency for the connection in number
           * of connection events.
           *
           * @param supervision_timeout Connection supervision timeout. Unit is
           * 10ms.
           *
           * @param master_clock_accuracy This parameter is only valid for a slave.
           * On a master it must be set to 0x00.
           *
           * @note: See Bluetooth 5 Vol 2 PartE: 7.7.65.10 LE enhanced connection
           * complete event.
           */
          virtual void on_enhanced_connection_complete(
              hci_error_code_t status,
              connection_handle_t connection_handle,
              connection_role_t own_role,
              connection_peer_address_type_t peer_address_type,
              const address_t &peer_address,
              const address_t &local_resolvable_private_address,
              const address_t &peer_resolvable_private_address,
              uint16_t connection_interval,
              uint16_t connection_latency,
              uint16_t supervision_timeout,
              clock_accuracy_t master_clock_accuracy
          ) = 0;
  
          /** Called on advertising report event.
           *
           * @param event_type Type of advertising used.
           * @param address_type Peer address type of advertiser.
           * @param address Peer address of advertiser.
           * @param primary_phy PHY used on the primary channels.
           * @param secondary_phy PHY used on secondary channels.
           * @param advertising_sid Set identification number.
           * @param tx_power Transmission power reported by the packet.
           * @param rssi Measured signal strength.
           * @param periodic_advertising_interval Interval of periodic advertising.
           * @param direct_address_type Directed advertising target address type.
           * @param direct_address Directed advertising target address.
           * @param data_length Advertising payload length.
           * @param data Advertising payload.
           *
           * @note: See Bluetooth 5 Vol 2 PartE: 7.7.65.13 LE extended advertising
           * report event.
           */
          virtual void on_extended_advertising_report(
              advertising_event_t event_type,
              const connection_peer_address_type_t *address_type,
              const address_t &address,
              phy_t primary_phy,
              const phy_t *secondary_phy,
              advertising_sid_t advertising_sid,
              advertising_power_t tx_power,
              rssi_t rssi,
              uint16_t periodic_advertising_interval,
              direct_address_type_t direct_address_type,
              const address_t &direct_address,
              uint8_t data_length,
              const uint8_t *data_size
          ) = 0;
  
          /** Called on advertising sync event.
           *
           * @param error SUCCESS if synchronisation was achieved.
           * @param sync_handle Advertising sync handle.
           * @param advertising_sid Advertising set identifier.
           * @param advertiser_address_type Peer address type.
           * @param advertiser_address Peer address.
           * @param advertiser_phy PHY used for advertisements.
           * @param periodic_advertising_interval Periodic advertising interval.
           * @param clock_accuracy Peer clock accuracy.
           */
          virtual void on_periodic_advertising_sync_established(
              pal::hci_error_code_t error,
              pal::sync_handle_t sync_handle,
              advertising_sid_t advertising_sid,
              connection_peer_address_type_t advertiser_address_type,
              const ble::address_t &advertiser_address,
              phy_t advertiser_phy,
              uint16_t periodic_advertising_interval,
              pal::clock_accuracy_t clock_accuracy
          ) = 0;
  
          /** Called after a periodic advertising report event.
           *
           * @param sync_handle Periodic advertising sync handle
           * @param tx_power TX power.
           * @param rssi Received signal strength.
           * @param data_status Status to indicate the completeness of the payload.
           * @param data_length Periodic advertisement payload length.
           * @param data Periodic advertisement payload.
           */
          virtual void on_periodic_advertising_report(
              sync_handle_t sync_handle,
              advertising_power_t tx_power,
              rssi_t rssi,
              advertising_data_status_t data_status,
              uint8_t data_length,
              const uint8_t *data
          ) = 0;
  
          /** Called on periodic advertising sync loss event.
           *
           * @param sync_handle Advertising sync handle'
           */
          virtual void on_periodic_advertising_sync_loss(
              sync_handle_t sync_handle
          ) = 0;
  
          /** Called when scanning times out.
           */
          virtual void on_scan_timeout() = 0;
  
          /** Called when advertising set stops advertising.
           *
           * @param status SUCCESS if connection has been established.
           * @param advertising_handle Advertising set handle.
           * @param advertising_handle Connection handle.
           * @param number_of_completed_extended_advertising_events Number of events created during before advertising end.
           */
          virtual void on_advertising_set_terminated(
              hci_error_code_t status,
              advertising_handle_t advertising_handle,
              connection_handle_t connection_handle,
              uint8_t number_of_completed_extended_advertising_events
          ) = 0;
  
          /** Called when a device receives a scan request from an active scanning device.
           *
           * @param advertising_handle Advertising set handle.
           * @param scanner_address_type Peer address type.
           * @param address Peer address.
           */
          virtual void on_scan_request_received(
              advertising_handle_t advertising_handle,
              connection_peer_address_type_t scanner_address_type,
              const address_t &address
          ) = 0;
  
          virtual void on_connection_update_complete(
              hci_error_code_t status,
              connection_handle_t connection_handle,
              uint16_t connection_interval,
              uint16_t connection_latency,
              uint16_t supervision_timeout
          ) = 0;
  
          virtual void on_remote_connection_parameter(
              connection_handle_t connection_handle,
              uint16_t connection_interval_min,
              uint16_t connection_interval_max,
              uint16_t connection_latency,
              uint16_t supervision_timeout
          ) = 0;
      };
  
      /**
       * Initialisation of the instance. An implementation can use this function
       * to initialise the subsystems needed to realize the operations of this
       * interface.
       *
       * This function has to be called before any other operations.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       */
      virtual ble_error_t initialize() = 0;
  
      /**
       * Termination of the instance. An implementation can use this function
       * to release the subsystems initialised to realise the operations of
       * this interface.
       *
       * After a call to this function, initialise should be called again to
       * allow use of the interface.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       */
      virtual ble_error_t terminate() = 0;
  
      /**
       * Return the public device address.
       *
       * @note The public device address is usually acquired at initialization and
       * stored in the instance.
       *
       * @return the public device address.
       */
      virtual address_t get_device_address() = 0;
  
      /**
       * Return the current random address.
       *
       * @note The random address is usually acquired at initialization and stored
       * in the instance.
       *
       * @return the random device address.
       */
      virtual address_t get_random_address() = 0;
  
      /**
       * Set the random address which will used be during scan, connection or
       * advertising process if the own address type selected is random.
       *
       * Changing the address during scan, connection or advertising process is
       * forbiden.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.4 LE set random address command.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       */
      virtual ble_error_t set_random_address(const address_t &address) = 0;
  
      /**
       * Set the random device address used by an advertising set.
       *
       * @pre No connectable advertising set should be enabled.
       *
       * @post The new random address should be used when @p advertising_set_handle
       * is enabled.
       *
       * @param advertising_handle Handle to the advertising set that will be
       * advertised with the address @p address.
       *
       * @param address The random address to use when @p advertising_set_handle
       * is in use.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note See Bluetooth 5 Vol 2, Part E: 7.8.52 LE Set Advertising Set Random
       * Address Command
       */
      virtual ble_error_t set_advertising_set_random_address(
          advertising_handle_t advertising_handle,
          const address_t &address
      ) = 0;
  
      /**
       * Set the advertising parameters which will be used during the advertising
       * process.
       *
       * @param advertising_interval_min: Minimum advertising interval which can
       * be used during undirected and low duty cycle directed advertising. This
       * parameter shall be less than or equal to advertising_interval_max. This
       * parameter shall be in the range [0x20 : 0x4000] where each unit is equal
       * to 0.625ms.
       * This parameter is not used by directed high duty cycle advertising.
       *
       * @param advertising_interval_max: Maximum advertising interval which can
       * be used during undirected and low duty cycle directed advertising. This
       * parameter shall be more than or equal to advertising_interval_min. This
       * parameter shall be in the range [0x20 : 0x4000] where each unit is equal
       * to 0.625ms.
       * This parameter is not used by directed high duty cycle advertising.
       *
       * @param advertising_type Packet type that is used during the
       * advertising process. Direct advertising require valid peer addresses
       * parameters and ignore the filter policy set.
       * If the High duty cycle advertising is used then the advertising parameter
       * intervals are ignored.
       *
       * @param own_address_type Own address type used during advertising.
       * If own address type is equal to RESOLVABLE_PRIVATE_ADDRESS_PUBLIC_FALLBACK
       * or RESOLVABLE_PRIVATE_ADDRESS_RANDOM_FALLBACK then the peer address
       * parameters (type and address) will be used to find the local IRK.
       *
       * @param peer_address_type Address type of the peer.
       * This parameter shall be valid if directed advertising is used (
       * ADV_DIRECT_IND or ADV_DIRECT_IND_LOW_DUTY_CYCLE). This parameter should
       * be valid if the own address type is equal to 0x02 or 0x03.
       * In other cases, this parameter is ignored.
       *
       * @param peer_address Public device address, Random device addres, Public
       * identity address or Random static identity address of the device targeted
       * by the advertising.
       * This parameter shall be valid if directed advertising is used (
       * ADV_DIRECT_IND or ADV_DIRECT_IND_LOW_DUTY_CYCLE). This parameter should
       * be valid if the own address type is equal to 0x02 or 0x03.
       * In other cases, this parameter is ignored.
       *
       * @param advertising_channel_map Map of the channel used to send
       * advertising data.
       *
       * @param advertising_filter_policy Filter policy applied during the
       * advertising process. The subsystem should use the whitelist to apply the
       * policy. This parameter is ignored if the advertising type is directed (
       * ADV_DIRECT_IND or ADV_DIRECT_IND_LOW_DUTY_CYCLE).
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.5 LE set advertising parameters
       * command.
       */
      virtual ble_error_t set_advertising_parameters(
          uint16_t advertising_interval_min,
          uint16_t advertising_interval_max,
          advertising_type_t advertising_type,
          own_address_type_t own_address_type,
          advertising_peer_address_type_t peer_address_type,
          const address_t &peer_address,
          advertising_channel_map_t advertising_channel_map,
          advertising_filter_policy_t advertising_filter_policy
      ) = 0;
  
      /**
       * Define the advertising parameters of an advertising set.
       *
       * @param advertising_handle Identify the advertising set being configured.
       *
       * @param event_properties Describe the type of advertising event and its
       * properties.
       *
       * @param primary_advertising_interval_min, primary_advertising_interval_max
       * Advertising interval range for undirected and low duty cycle advertising.
       * This parameter is not considered if @p event_properties.high_duty_cycle is
       * set.
       *
       * @param primary_advertising_channel_map Map of the advertising channel to
       * use while advertising.
       *
       * @param own_address_type The type of address being used by the local
       * controller. If this parameter is a resolvable address then the peer
       * address should be an identity address.
       *
       * @param peer_address_type, peer_address Address of the peer. This parameter
       * is not evaluated if @p event_properties.directed is not set.
       *
       * @param advertising_filter_policy Filter applied to scan and connection
       * requests. It is ignored for directed advertising (@p
       * event_properties.directed set).
       *
       * @param advertising_power Maximum power level used during advertising.
       * The controller select a power level lower than or equal to this value.
       * The special value 127 should be used if the host as no preference towards
       * the transmit power used.
       *
       * @param primary_advertising_phy PHY used to transmit data on the primary
       * advertising channel. Accepted values are: phy_t::LE_1M and phy_t::LE_CODED.
       *
       * @param secondary_advertising_max_skip Maximum number of advertising events
       * that can be skipped before the AUX_ADV_IND can be sent.
       *
       * @param secondary_phy PHY used to transmit data on the secondary advertising
       * channel.
       *
       * @param advertising_sid 4bit value identifying the advertising set over the
       * air. It is not used by legacy advertising.
       *
       * @param scan_request_notification Indicate if the host wants to receive
       * scan request notification events.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.53 LE Set Extended Advertising
       * Parameters Command.
       *
       * @note If the advertising set does not exist on the controller, it is
       * created.
       *
       * @pre @p advertising_handle should not be enabled when this command is
       * issued.
       */
      virtual ble_error_t set_extended_advertising_parameters(
          advertising_handle_t advertising_handle,
          advertising_event_properties_t event_properties,
          advertising_interval_t primary_advertising_interval_min,
          advertising_interval_t primary_advertising_interval_max,
          advertising_channel_map_t primary_advertising_channel_map,
          own_address_type_t own_address_type,
          advertising_peer_address_type_t peer_address_type,
          const address_t &peer_address,
          advertising_filter_policy_t advertising_filter_policy,
          advertising_power_t advertising_power,
          phy_t primary_advertising_phy,
          uint8_t secondary_advertising_max_skip,
          phy_t secondary_phy,
          uint8_t advertising_sid,
          bool scan_request_notification
      ) = 0;
  
      /**
       * Configure periodic advertising parameters of an advertising set.
       *
       * @pre The advertising handle must exist on the controller @see
       * set_extended_advertising_parameters .
       *
       * @pre Periodic advertising of @p advertising_handle should not be enabled
       * when this function is called.
       *
       * @pre The advertising set identified by @p advertising_handle should not
       * be configured as anonymous advertising.
       *
       * @param advertising_handle The advertising set being configured.
       *
       * @param periodic_advertising_min, periodic_advertising_max Advertising
       * interval range for periodic advertising of this set.
       *
       * @param advertise_power If true, the transmission power should be included
       * in the advertising PDU.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.61 LE Set Periodic Advertising
       * Parameters Command
       */
      virtual ble_error_t set_periodic_advertising_parameters(
          advertising_handle_t advertising_handle,
          periodic_advertising_interval_t periodic_advertising_min,
          periodic_advertising_interval_t periodic_advertising_max,
          bool advertise_power
      ) = 0;
  
      /**
       * Set the data sends in advertising packet. If the advertising is
       * currently enabled, the data shall be used when a new advertising packet
       * is issued.
       *
       * @param advertising_data_length Number of significant bytes in the
       * advertising data.
       *
       * @param advertising_data The data sends in advertising packets. Non
       * significant bytes shall be equal to 0.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.5 LE set advertising data
       * command.
       */
      virtual ble_error_t set_advertising_data(
          uint8_t advertising_data_length,
          const advertising_data_t &advertising_data
      ) = 0;
  
      /**
       * Set data in advertising PDUs.
       *
       * @note this command can be called at anytime, whether the advertising set
       * is enabled or not.
       *
       * @note the extended scan response can be set in one or more command.
       *
       * @pre @p advertising_handle should exist. To create it call
       * set_extended_scan_parameters.
       *
       * @post The data inserted is used for subsequent advertising events.
       *
       * @param advertising_handle The handle identifying the advertising set
       * associated with the data.
       *
       * @param operation Description of the operation to apply to @p
       * advertising_handle data.
       *
       * @param minimize_fragmentation Hint for the controller to minimize
       * fragmentation of data sent over the air.
       *
       * @param advertising_data_size, advertising_data The data to associate to @p
       * advertising_handle.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.54 LE set extended advertising
       * data command.
       */
      virtual ble_error_t set_extended_advertising_data(
          advertising_handle_t advertising_handle,
          advertising_fragment_description_t operation,
          bool minimize_fragmentation,
          uint8_t advertising_data_size,
          const uint8_t *advertising_data
      ) = 0;
  
      /**
       * Set the data used in periodic advertising PDUs.
       *
       * @note the extended scan response can be set in one or more command.
       *
       * @pre @p advertising_handle must exist. See set_extended_advertising_parameters.
       *
       * @pre @p advertising_handle must be configured for periodic advertising.
       * See set_periodic_advertising_parameters .
       *
       * @param advertising_handle The handle identifying the advertising set
       * associated with the data.
       *
       * @param fragment_description Description of the operation to apply to @p
       * advertising_handle data.
       *
       * @param advertising_data_size, advertising_data The data to associate to @p
       * advertising_handle.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.62 LE set periodic advertising
       * data command.
       */
      virtual ble_error_t set_periodic_advertising_data(
          advertising_handle_t advertising_handle,
          advertising_fragment_description_t fragment_description,
          uint8_t advertising_data_size,
          const uint8_t *advertising_data
      ) = 0;
  
      /**
       * Set the data sends in scan response packets. If the advertising is
       * currently enabled, the data shall be used when a new scan response is
       * issued.
       *
       * @param scan_response_data_length Number of significant bytes in the
       * scan response data.
       *
       * @param scan_response_data The data sends in scan response packets. Non
       * significant bytes shall be equal to 0.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.8 LE set scan response data
       * command.
       */
      virtual ble_error_t set_scan_response_data(
          uint8_t scan_response_data_length,
          const advertising_data_t &scan_response_data
      ) = 0;
  
      /**
       * Set the data sends in extended scan response packets.  If the advertising
       * is currently enabled, the data shall be used when a new extended scan
       * response is issued.
       *
       * @note the extended scan response can be set in one or more command.
       *
       * @param advertising_handle The advertising handle that owns the scan
       * response data.
       *
       * @param operation Description of the operation to apply to @p
       * advertising_handle data.
       *
       * @param minimize_fragmentation Hint for the controller to minimize
       * fragmentation of data sent over the air.
       *
       * @param scan_response_data_size, scan_response_data The data to associate
       * to @p advertising_handle.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.55 LE set extended scan response
       * data command.
       */
      virtual ble_error_t set_extended_scan_response_data(
          advertising_handle_t advertising_handle,
          advertising_fragment_description_t operation,
          bool minimize_fragmentation,
          uint8_t scan_response_data_size,
          const uint8_t *scan_response_data
      ) = 0;
  
      /**
       * Start or stop advertising.
       *
       * The process use advertising and scan response data set with
       * set_advertising_data and set_scan_response_data while the parameters used
       * are the one set by set_advertising_parameters.
       *
       * The advertising shall continue until:
       *     - The advertising is manually disabled (advertising_enable(false)).
       *     - A connection is created.
       *     - Time out in case of high duty cycle directed advertising.
       *
       * If the random address has not been set and the advertising parameter
       * own_address_type is set to 0x01 then the procedure shall fail.
       *
       * If the random address has not been set and the advertising parameter
       * own_address_type is set to RESOLVABLE_PRIVATE_ADDRESS_RANDOM_FALLBACK and
       * the peer address is not in the resolving list then the procedure shall
       * fail.
       *
       * @param enable If true start the advertising process, if the process was
       * already runing and own_address_type is equal to 0x02 or 0x03, the
       * subsystem can change the random address.
       * If false and the advertising is running then the process should be
       * stoped.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.9 LE set advertising enable
       * command.
       *
       * @note If the advertising type is ADV_DIRECT_IND and the connection is not
       * created during the time allowed to the procedure then a
       * ConnectionComplete event shall be emmited with its error code set to
       * ADVERTISING_TIMEOUT.
       *
       * @note Successfull connection shall emit a ConnectionComplete event. It
       * also means advertising is disabled.
       */
      virtual ble_error_t advertising_enable(bool enable) = 0;
  
      /**
       * Start of stop advertising of extended advertising sets.
       *
       * @pre advertising handles present in @p handles must exist.
       *
       * @pre advertising or scan response data must be complete for advertising
       * handles in @p handles.
       *
       * @note Disabling the advertising set identified by @p handle[i] does not
       * disable any periodic advertising associated with that set.
       *
       * @param enable If true, start advertising of the advertising sets pointed
       * by @p handles. If false stop advertising for the advertising sets pointed
       * by @p handles.
       *
       * @param number_of_sets Number of advertising sets concerned by the operation.
       * @p handles, @p durations and @p max_extended_advertising_events should
       * contain @p number_of_sets elements.
       *
       * @param handles Handle of advertising sets to start or stop.
       *
       * @param durations Advertising duration for @p handle. The unit is 10ms and
       * the special value 0x000 disable advertising timeout.
       *
       * @param max_extended_advertising_events Maximum number of extended
       * advertising events the controller must attempt to send prior to
       * terminating the extended advertising. The special value 0 indicate that
       * there is no maximum.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.56 LE extended advertising enable
       * command.
       */
      virtual ble_error_t extended_advertising_enable(
          bool enable,
          uint8_t number_of_sets,
          const advertising_handle_t *handles,
          const uint16_t *durations,
          const uint8_t *max_extended_advertising_events
      ) = 0;
  
      /**
       * Enable or disable periodic advertising of an advertising set.
       *
       * @param enable If true enable periodic advertising of @p advertising_handle
       * otherwise disable it.
       *
       * @param advertising_handle Handle to the advertising set to enable or
       * disable.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.63 LE periodic advertising enable
       * command.
       */
      virtual ble_error_t periodic_advertising_enable(
          bool enable,
          advertising_handle_t advertising_handle
      ) = 0;
  
      /**
       * Query the maximum data length the controller supports in an advertising
       * set.
       *
       * @return The length in byte the controller can support in an advertising
       * set.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.57 LE read maximum advertising
       * data length command.
       */
      virtual uint16_t get_maximum_advertising_data_length() = 0;
  
      /**
       * Query the maximum data length the controller supports in an advertising set
       * using connectable advertising.
       *
       * @return The length in byte the controller can support in an advertising set
       * for connectable advertising.
       */
      virtual uint16_t get_maximum_connectable_advertising_data_length() = 0;
  
      /**
       * Query the maximum payload length for a single HCI packet carrying partial
       * (or complete if it fits) data for advertising set.
       *
       * @return Max size of the HCI packet transporting the data.
       */
      virtual uint8_t get_maximum_hci_advertising_data_length() = 0;
  
      /**
       * Query the maximum number of concurrent advertising sets that is supported
       * by the controller.
       *
       * @return The number of concurrent advertising sets supported by the
       * controller.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.58 LE number of supported
       * advertising sets command.
       */
      virtual uint8_t get_max_number_of_advertising_sets() = 0;
  
      /**
       * Remove an advertising set from the controller.
       *
       * After this operation, configuration and data associated with @p
       * advertising_handle are lost.
       *
       * @pre @p advertising_handle must exist.
       *
       * @pre Advertising of @p advertising_handle must be disabled.
       *
       * @param advertising_handle The advertising handle to destroy.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.59 LE remove advertising set
       * command.
       */
      virtual ble_error_t remove_advertising_set(
          advertising_handle_t advertising_handle
      ) = 0;
  
      /**
       * Remove all advertising sets maintained by the controller.
       *
       * @pre Advertising of all advertising sets must be disabled.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.60 LE clear advertising sets
       * command.
       */
      virtual ble_error_t clear_advertising_sets() = 0;
  
  
      /**
       * Set the parameter of the scan process.
       *
       * This command shall not be effective when the scanning process is running.
       *
       * @param active_scanning If true the subsystem does active scanning and
       * the bluetooth subsystem shall send scanning PDUs. It shall also listen
       * to scan responses. If false no scanning PDUs are sent during the scan
       * process.
       *
       * @param scan_interval The time interval between two subsequent LE scans in
       * unit of 0.625ms. This parameter shall be in the range [0x0004 : 0x4000].
       *
       * @param scan_window Duration of the LE scan. It shall be less than or
       * equal to scan_interval value. This parameter shall be in the range
       * [0x0004 : 0x4000] and is in unit of 0.625ms.
       *
       * @param own_address_type Own address type used in scan request packets.
       *
       * @param filter_policy Filter policy applied when scanning.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.10 LE set scan parameters
       * command.
       */
      virtual ble_error_t set_scan_parameters(
          bool active_scanning,
          uint16_t scan_interval,
          uint16_t scan_window,
          own_address_type_t own_address_type,
          scanning_filter_policy_t filter_policy
      ) = 0;
  
      /**
       * Set extended scan parameters to be used on advertising channels.
       *
       * @param own_address_type Type of the address used in scan requests.
       *
       * @param filter_policy Scanning filter policy.
       *
       * @param scanning_phys The phy affected by the parameter change. Just
       * LE_1M and LE_CODED can be set. If two phys are set then @p active_scanning,
       * @p scan_interval and @p scan_window must contain two elements. The first
       * being applied to LE_1M and the second being applied to LE_CODED.
       *
       * @param active_scanning If true, active scanning is used for the
       * correcponding PHY.
       *
       * @param scan_interval Interval between two subsequent scan. This parameter
       * shall be in the range [0x0004 : 0x4000] and is in unit of 0.625ms.
       *
       * @param scan_window Duration of the LE scan. It shall be less than or
       * equal to scan_interval value. This parameter shall be in the range
       * [0x0004 : 0x4000] and is in unit of 0.625ms.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.64 LE set extended scan parameters
       * command.
       */
      virtual ble_error_t set_extended_scan_parameters(
          own_address_type_t own_address_type,
          scanning_filter_policy_t filter_policy,
          phy_set_t scanning_phys,
          const bool *active_scanning,
          const uint16_t *scan_interval,
          const uint16_t *scan_window
      ) = 0;
  
      /**
       * Start/stop scanning process.
       *
       * Parameters of the scanning process shall be set before the scan launch
       * by using the function set_scan_parameters.
       *
       * @parameter enable Start the scanning process if true and stop it if
       * false. If the scan process is already started, enabling it again will
       * only update the duplicate filtering; based on the new parameter.
       *
       * @parameter filter_duplicates Enable duplicate filtering if true,
       * otherwise disable it.
       *
       * @attention advertising data or scan response data is not considered
       * significant when determining duplicate advertising reports.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.11 LE set scan enable command.
       */
      virtual ble_error_t scan_enable(
          bool enable,
          bool filter_duplicates
      ) = 0;
  
      /**
       * Enable or disable extended scanning.
       *
       * @param enable If true enable scanning and disable it otherwise.
       *
       * @param filter_duplicates If true filter out duplicate scan reports.
       *
       * @param duration Duration of the scan operation. The unit is 10ms and
       * the special value 0 indicate continuous scan until explicitly disabled.
       *
       * @param period Interval between two scan operations. The unit is 1.28s and
       * the special value 0 can be used to disable periodic scanning. If @p
       * filter_duplicates is equal to duplicates_filter_t::PERIODIC_RESET then
       * the duplicate cache is reset whenever a scan operation starts.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.65 LE set extended scan enable
       * command.
       */
      virtual ble_error_t extended_scan_enable(
          bool enable,
          duplicates_filter_t filter_duplicates,
          uint16_t duration,
          uint16_t period
      ) = 0;
  
      /**
       * Synchronize an observer with a periodic advertising broadcaster.
       *
       * One the synchronization is establish the function
       * EventHandler::on_periodic_advertising_sync_established is called and for
       * every periodic advertising received is reported via the function
       * EventHandler::on_periodic_advertising_report .
       *
       * @param use_periodic_advertiser_list Determine if the periodic advertiser
       * list is used or ignored.
       *
       * @param advertising_sid SID to sync with.
       *
       * @param peer_address_type, peer_address Address of the advertiser. If @p
       * use_periodic_advertiser_list is true then these parameters are ignored.
       *
       * @param allowed_skip Number of periodic advertisement that can be skipped
       * after a successful receive by the local device.
       *
       * @param sync_timeout Specifies the maximum permitted time between two
       * successful receives. If this time is exceeded then the synchronization is
       * considered lost and EventHandler::on_periodic_advertising_loss is called.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.67 LE periodic advertising create
       * sync command.
       */
      virtual ble_error_t periodic_advertising_create_sync(
          bool use_periodic_advertiser_list,
          uint8_t advertising_sid,
          peer_address_type_t peer_address_type,
          const address_t &peer_address,
          uint16_t allowed_skip,
          uint16_t sync_timeout
      ) = 0;
  
      /**
       * Cancel the establishment of synchronization with a periodic advertising
       * broadcaster.
       *
       * @pre There should be an ongoing sync establishment operation.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.68 LE periodic advertising create
       * sync cancel command.
       */
      virtual ble_error_t cancel_periodic_advertising_create_sync() = 0;
  
      /**
       * Stop reception of the periodic advertising identified by @p sync_handle.
       *
       * @param sync_handle The handle identifying the periodic advertiser. It is
       * obtained when EventHandler::on_periodic_advertising_sync_established is
       * called.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.69 LE periodic advertising
       * terminate sync command.
       */
      virtual ble_error_t periodic_advertising_terminate_sync(
          sync_handle_t sync_handle
      ) = 0;
  
      /**
       * Add a device to the periodic advertiser list stored in the controller.
       * This list may be used to create a periodic advertiser sync.
       *
       * @pre The device should not be in the periodic advertiser list.
       *
       * @pre Create sync operation should not be pending
       *
       * @pre The periodic advertising list of the controller should not be full.
       *
       * @param advertiser_address_type The address type of the device to add.
       *
       * @param advertiser_address The address value of the device to add.
       *
       * @param advertising_sid The SID field used to identify periodic advertising
       * from the device.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.70 LE add device to periodic
       * advertising list command.
       */
      virtual ble_error_t add_device_to_periodic_advertiser_list(
          advertising_peer_address_type_t advertiser_address_type,
          const address_t &advertiser_address,
          uint8_t advertising_sid
      ) = 0;
  
      /**
       * Remove a device from the periodic advertiser list.
       *
       * @pre Create sync operation should not be pending
       *
       * @param advertiser_address_type The address type of the device to remove.
       *
       * @param advertiser_address The address value of the device to remove.
       *
       * @param advertising_sid The SID field used to identify periodic advertising
       * from the device.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.71 LE remove device from periodic
       * advertising list command.
       */
      virtual ble_error_t remove_device_from_periodic_advertiser_list(
          advertising_peer_address_type_t advertiser_address_type,
          const address_t &advertiser_address,
          uint8_t advertising_sid
      ) = 0;
  
      /**
       * Clear all devices from the list of periodic advertisers.
       *
       * @pre Create sync operation should not be pending
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.72 LE clear periodic advertising
       * list command.
       */
      virtual ble_error_t clear_periodic_advertiser_list() = 0;
  
      /**
       * Return the total number of entries that can be stored by the periodic
       * advertiser list.
       *
       * @return The capacity of the periodic advertiser list.
       *
       * @note We (wrongfully) assume that value doesn't change over time.
       */
      virtual uint8_t read_periodic_advertiser_list_size() = 0;
  
      /**
       * Create a new le connection to a connectable advertiser.
       *
       * @param scan_interval Hint to the le subsystem indicating how
       * frequently it should scan for the peer address. It represent the time
       * interval between two subsequent scan for the peer. It shall be in the
       * range [0x0004 : 0x4000] and the time is in unit of 0.625ms.
       *
       * @param scan_window Hint to the le subsystem indicating for how long it
       * should scan during a scan interval. The value shall be smaller or equal
       * to scan_interval. If it is equal to scan_interval then scanning should
       * run continuously. It shall be in the range [0x0004 : 0x4000] and the time
       * is in unit of 0.625ms.
       *
       * @param initiator_policy Used to determine if the whitelist is used to
       * determine the address to connect to. If the whitelist is not used, the
       * connection shall be made against an advertiser matching the peer_address
       * and the peer_address_type parameters. Otherwise those parameters are
       * ignored.
       *
       * @param peer_address_type Type of address used by the advertiser. Not used
       * if initiator_policy use the whitelist.
       *
       * @param Address used by the advertiser in its advertising packets. Not
       * used if initiator_policy use the whitelist.
       *
       * @param own_address_type Type of address used in the connection request
       * packet.
       *
       * @param connection_interval_min Minimum interval between two connection
       * events allowed for the connection. It shall be less than or equal to
       * connection_interval_max. This value shall be in range [0x0006 : 0x0C80]
       * and is in unit of 1.25ms.
       *
       * @param connection_interval_max Maximum interval between two connection
       * events allowed for the connection. It shall be greater than or equal to
       * connection_interval_min. This value shall be in range [0x0006 : 0x0C80]
       * and is in unit of 1.25ms.
       *
       * @param connection_latency Number of connection events the slave can drop
       * if it has nothing to communicate to the master. This value shall be in
       * the range [0x0000 : 0x01F3].
       *
       * @param supervision_timeout Link supervision timeout for the connection.
       * It shall be larger than:
       *        (1 + connection_latency) * connection_interval_max * 2
       * Note: connection_interval_max is in ms in this formulae.
       * Everytime the master or the slave receive a valid packet from the peer,
       * the supervision timer is reset. If the supervision timer reaches
       * supervision_timeout then the connection is considered lost and a
       * disconnect event shall be emmited.
       * This value shall be in the range [0x000A : 0x0C80] and is in unit of 10
       * ms.
       *
       * @param minimum_connection_event_length Informative parameter of the
       * minimum length a connection event. It shall be less than or equal to
       * maximum_connection_event_length. It shall be in the range
       * [0x0000 : 0xFFFF]. It should also be less than the expected connection
       * interval. The unit is 0.625ms.
       *
       * @param maximum_connection_event_length Informative parameter of the
       * maximum length a connection event. It shall be more than or equal to
       * minimum_connection_event_length. It shall be in the range
       * [0x0000 : 0xFFFF]. It should also be less than the expected connection
       * interval. The unit is 0.625ms.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.12 LE create connection command.
       */
      virtual ble_error_t create_connection(
          uint16_t scan_interval,
          uint16_t scan_window,
          initiator_policy_t initiator_policy,
          connection_peer_address_type_t peer_address_type,
          const address_t &peer_address,
          own_address_type_t own_address_type,
          uint16_t connection_interval_min,
          uint16_t connection_interval_max,
          uint16_t connection_latency,
          uint16_t supervision_timeout,
          uint16_t minimum_connection_event_length,
          uint16_t maximum_connection_event_length
      ) = 0;
  
      /**
       * Create a new le connection to a connectable advertiser.
       *
       * @param initiator_policy Used to determine if the whitelist is used to
       * determine the address to connect to. If the whitelist is not used, the
       * connection shall be made against an advertiser matching the peer_address
       * and the peer_address_type parameters. Otherwise those parameters are
       * ignored.
       *
       * @param own_address_type Type of address used in the connection request
       * packet.
       *
       * @param peer_address_type Type of address used by the advertiser. Not used
       * if initiator_policy use the whitelist.
       *
       * @param peer_address Address used by the advertiser in its advertising
       * packets. Not used if initiator_policy use the whitelist.
       *
       * @param initiating_phys Indicates the advertising PHYs and the controller
       * may use find the target and establish the connection. Subsequent
       * parameters are arrays of value associated with phys present in @p
       * initiating_phys. The order of phys is 1M, 2M, Coded.
       *
       * @param scan_intervals Hint to the le subsystem indicating how
       * frequently it should scan for the peer address. It represent the time
       * interval between two subsequent scan for the peer. It shall be in the
       * range [0x0004 : 0x4000] and the time is in unit of 0.625ms.
       *
       * @param scan_windows Hint to the le subsystem indicating for how long it
       * should scan during a scan interval. The value shall be smaller or equal
       * to scan_interval. If it is equal to scan_interval then scanning should
       * run continuously. It shall be in the range [0x0004 : 0x4000] and the time
       * is in unit of 0.625ms.
       *
       * @param connection_intervals_min Minimum interval between two connection
       * events allowed for the connection. It shall be less than or equal to
       * connection_interval_max. This value shall be in range [0x0006 : 0x0C80]
       * and is in unit of 1.25ms.
       *
       * @param connection_intervals_max Maximum interval between two connection
       * events allowed for the connection. It shall be greater than or equal to
       * connection_interval_min. This value shall be in range [0x0006 : 0x0C80]
       * and is in unit of 1.25ms.
       *
       * @param connection_latencies Number of connection events the slave can drop
       * if it has nothing to communicate to the master. This value shall be in
       * the range [0x0000 : 0x01F3].
       *
       * @param supervision_timeouts Link supervision timeout for the connection.
       * It shall be larger than:
       *        (1 + connection_latency) * connection_interval_max * 2
       * Note: connection_interval_max is in ms in this formulae.
       * Everytime the master or the slave receive a valid packet from the peer,
       * the supervision timer is reset. If the supervision timer reaches
       * supervision_timeout then the connection is considered lost and a
       * disconnect event shall be emmited.
       * This value shall be in the range [0x000A : 0x0C80] and is in unit of 10
       * ms.
       *
       * @param minimum_connection_event_lengths Informative parameter of the
       * minimum length a connection event. It shall be less than or equal to
       * maximum_connection_event_length. It shall be in the range
       * [0x0000 : 0xFFFF]. It should also be less than the expected connection
       * interval. The unit is 0.625ms.
       *
       * @param maximum_connection_event_lengths Informative parameter of the
       * maximum length a connection event. It shall be more than or equal to
       * minimum_connection_event_length. It shall be in the range
       * [0x0000 : 0xFFFF]. It should also be less than the expected connection
       * interval. The unit is 0.625ms.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.66 LE extended create connection
       * command.
       */
      virtual ble_error_t extended_create_connection(
          initiator_policy_t initiator_policy,
          own_address_type_t own_address_type,
          peer_address_type_t peer_address_type,
          const address_t &peer_address,
          phy_set_t initiating_phys,
          const uint16_t *scan_intervals,
          const uint16_t *scan_windows,
          const uint16_t *connection_intervals_min,
          const uint16_t *connection_intervals_max,
          const uint16_t *connection_latencies,
          const uint16_t *supervision_timeouts,
          const uint16_t *minimum_connection_event_lengths,
          const uint16_t *maximum_connection_event_lengths
      ) = 0;
  
      /**
       * Cancel the ongoing connection creation process.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.13 LE create connection cancel
       * command.
       */
      virtual ble_error_t cancel_connection_creation() = 0;
  
      /**
       * Return the number of total whitelist entries that can be stored in the
       * le subsystem.
       *
       * @note The value returned can change over time.
       *
       * @return The number of entries that can be stored in the LE subsystem. It
       * range from 0x01 to 0xFF.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.14 LE read white list size
       * command.
       */
      virtual uint8_t read_white_list_capacity() = 0;
  
      /**
       * Clear the whitelist stored in the LE subsystem.
       *
       * @attention This command shall not be issued if the whitelist is being
       * used by the advertising, scanning or connection creation procedure.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.15 LE clear white list command.
       */
      virtual ble_error_t clear_whitelist() = 0;
  
      /**
       * Add a device to the LE subsystem Whitelist.
       *
       * @param address_type address_type Type of the address to add in the
       * whitelist.
       *
       * @param address Address of the device.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @attention This command shall not be issued if the whitelist is being
       * used by the advertising, scanning or connection creation procedure.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.16 LE add device to white list
       * command.
       */
      virtual ble_error_t add_device_to_whitelist(
          whitelist_address_type_t address_type,
          address_t address
      ) = 0;
  
      /**
       * Remove a device from the LE subsystem Whitelist.
       *
       * @param address_type address_type Type of the address of the device to
       * remove from the whitelist.
       *
       * @param address Address of the device to remove from the whitelist
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @attention This command shall not be issued if the whitelist is being
       * used by the advertising, scanning or connection creation procedure.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.17 LE remove device from white
       * list command.
       */
      virtual ble_error_t remove_device_from_whitelist(
          whitelist_address_type_t address_type,
          address_t address
      ) = 0;
  
      /**
       * Start a connection update procedure.
       *
       * This procedure change the parameter used for a connection it can be
       * master or slave initiated.
       *
       * The peer will received a connection parameters request and will either
       * accept or reject the new parameters for the connection.
       *
       * Once the peer response has been received, the procedure ends and a
       * Connection update complete event is emmited.
       *
       * @param connection Handle of the connection.
       *
       * @param connection_interval_min Minimum interval between two connection
       * events allowed for the connection. It shall be less than or equal to
       * connection_interval_max. This value shall be in range [0x0006 : 0x0C80]
       * and is in unit of 1.25ms.
       *
       * @param connection_interval_max Maximum interval between two connection
       * events allowed for the connection. It shall be greater than or equal to
       * connection_interval_min. This value shall be in range [0x0006 : 0x0C80]
       * and is in unit of 1.25ms.
       *
       * @param connection_latency Number of connection events the slave can drop
       * if it has nothing to communicate to the master. This value shall be in
       * the range [0x0000 : 0x01F3].
       *
       * @param supervision_timeout Link supervision timeout for the connection.
       * It shall be larger than:
       *        (1 + connection_latency) * connection_interval_max * 2
       * Note: connection_interval_max is in ms in this formulae.
       * Everytime the master or the slave receive a valid packet from the peer,
       * the supervision timer is reset. If the supervision timer reaches
       * supervision_timeout then the connection is considered lost and a
       * disconnect event shall be emmited.
       * This value shall be in the range [0x000A : 0x0C80] and is in unit of 10
       * ms.
       *
       * @param minimum_connection_event_length Informative parameter of the
       * minimum length a connection event. It shall be less than or equal to
       * maximum_connection_event_length. It shall be in the range
       * [0x0000 : 0xFFFF]. It should also be less than the expected connection
       * interval. The unit is 0.625ms.
       *
       * @param maximum_connection_event_length Informative parameter of the
       * maximum length a connection event. It shall be more than or equal to
       * minimum_connection_event_length. It shall be in the range
       * [0x0000 : 0xFFFF]. It should also be less than the expected connection
       * interval. The unit is 0.625ms.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.18 LE Connection update command.
       *
       */
      virtual ble_error_t connection_parameters_update(
          connection_handle_t connection,
          uint16_t connection_interval_min,
          uint16_t connection_interval_max,
          uint16_t connection_latency,
          uint16_t supervision_timeout,
          uint16_t minimum_connection_event_length,
          uint16_t maximum_connection_event_length
      ) = 0;
  
      /**
       * Accept connection parameter request.
       *
       * This command sends a positive response to a connection parameter request
       * from a peer.
       *
       * @param connection Handle of the connection.
       *
       * @param connection_interval_min Minimum interval between two connection
       * events allowed for the connection. It shall be less than or equal to
       * connection_interval_max. This value shall be in range [0x0006 : 0x0C80]
       * and is in unit of 1.25ms.
       *
       * @param connection_interval_max Maximum interval between two connection
       * events allowed for the connection. It shall be greater than or equal to
       * connection_interval_min. This value shall be in range [0x0006 : 0x0C80]
       * and is in unit of 1.25ms.
       *
       * @param connection_latency Number of connection events the slave can drop
       * if it has nothing to communicate to the master. This value shall be in
       * the range [0x0000 : 0x01F3].
       *
       * @param supervision_timeout Link supervision timeout for the connection.
       * It shall be larger than:
       *        (1 + connection_latency) * connection_interval_max * 2
       * Note: connection_interval_max is in ms in this formulae.
       * Everytime the master or the slave receive a valid packet from the peer,
       * the supervision timer is reset. If the supervision timer reaches
       * supervision_timeout then the connection is considered lost and a
       * disconnect event shall be emmited.
       * This value shall be in the range [0x000A : 0x0C80] and is in unit of 10
       * ms.
       *
       * @param minimum_connection_event_length Informative parameter of the
       * minimum length a connection event. It shall be less than or equal to
       * maximum_connection_event_length. It shall be in the range
       * [0x0000 : 0xFFFF]. It should also be less than the expected connection
       * interval. The unit is 0.625ms.
       *
       * @param maximum_connection_event_length Informative parameter of the
       * maximum length a connection event. It shall be more than or equal to
       * minimum_connection_event_length. It shall be in the range
       * [0x0000 : 0xFFFF]. It should also be less than the expected connection
       * interval. The unit is 0.625ms.
       *
       * @note Usually parameters of this function match the connection parameters
       * received in the connection parameter request event.
       *
       * @attention: Once the new connection parameters are in used a Connection
       * Update Complete event shall be emmited.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.31 LE remote connection parameter
       * request reply command.
       */
      virtual ble_error_t accept_connection_parameter_request(
          connection_handle_t connection_handle,
          uint16_t interval_min,
          uint16_t interval_max,
          uint16_t latency,
          uint16_t supervision_timeout,
          uint16_t minimum_connection_event_length,
          uint16_t maximum_connection_event_length
      ) = 0;
  
      /**
       * Reject a connection parameter update request.
       *
       * @param connection_handle handle to the peer which has issued the
       * connection parameter request.
       *
       * @param rejection_reason Indicate to the peer why the proposed connection
       * parameters were rejected.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.32 LE Remote Connection Parameter
       * Request Negative Reply Command.
       */
      virtual ble_error_t reject_connection_parameter_request(
          connection_handle_t connection_handle,
          hci_error_code_t rejection_reason
      ) = 0;
  
      /**
       * Start a disconnection procedure.
       *
       * Once the procedure is complete it should emit a disconnection complete
       * event.
       *
       * @param connection Handle of the connection to terminate.
       *
       * @param disconnection_reason Indicates the reason for ending the
       * connection.
       *
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       *
       * @note: See Bluetooth 5 Vol 2 PartE: 7.1.6 disconenct command.
       */
      virtual ble_error_t disconnect(
          connection_handle_t connection,
          disconnection_reason_t disconnection_reason
      ) = 0;
  
      /** Check if privacy feature is supported by implementation
       *  
       * @return true if privacy is supported, false otherwise.
       * 
       * @note: See Bluetooth 5 Vol 3 Part C: 10.7 Privacy feature.
       */
      virtual bool is_privacy_supported() = 0;
  
      /** Enable or disable private addresses resolution
       *
       * @param enable whether to enable private addresses resolution
       *  
       * @return BLE_ERROR_NONE if the request has been successfully sent or the
       * appropriate error otherwise.
       * 
       * @note: See Bluetooth 5 Vol 2 PartE: 7.8.44 LE Set Address Resolution Enable command.
       */
      virtual ble_error_t set_address_resolution(
          bool enable
      ) = 0;
  
      /**
       * Checked support for a feature in the link controller.
       *
       * @param feature feature to be checked.
       * @return TRUE if feature is supported.
       */
      virtual bool is_feature_supported(
          controller_supported_features_t feature
      ) = 0;
  
      /**
      * @see Gap::readPhy
      */
      virtual ble_error_t read_phy(connection_handle_t connection) = 0;
  
      /**
      * @see Gap::setPreferredPhys
      */
      virtual ble_error_t set_preferred_phys(
          const phy_set_t &tx_phys,
          const phy_set_t &rx_phys
      ) = 0;
  
      /**
      * @see Gap::setPhy
      */
      virtual ble_error_t set_phy(
          connection_handle_t connection,
          const phy_set_t &tx_phys,
          const phy_set_t &rx_phys,
          coded_symbol_per_bit_t coded_symbol
      ) = 0;
  
      /**
       * Register a callback which will handle Gap events.
       *
       * @param cb The callback object which will handle Gap events from the
       * LE subsystem.
       * It accept a single parameter in input: The event received.
       */
      void when_gap_event_received(mbed::Callback<void(const GapEvent &)> cb)
      {
          _gap_event_cb = cb;
      }
  
  public:
      /**
      * Sets the event handler that us called by the PAL porters to notify the stack of events
      * which will in turn be passed onto the user application when appropriate.
      *
      * @param[in] event_handler the new event handler interface implementation. Memory
      * owned by caller who is responsible for updating this pointer if interface changes.
      */
      void set_event_handler(EventHandler *event_handler)
      {
          _pal_event_handler = event_handler;
      }
  
      EventHandler *get_event_handler()
      {
          return _pal_event_handler;
      }
  
  protected:
      EventHandler *_pal_event_handler;
  
  protected:
      Gap() : _pal_event_handler(NULL)
      {
      }
  
      virtual ~Gap()
      {
      }
  
      /**
       * Implementation shall call this function whenever the LE subsystem
       * generate a Gap event.
       *
       * @param gap_event The event to emit to higher layer.
       */
      void emit_gap_event(const GapEvent &gap_event)
      {
          if (_gap_event_cb) {
              _gap_event_cb(gap_event);
          }
      }
  
  public:
      /**
       * Create an ALL_PHYS parameter used in LE Set PHY Command
       * and LE Set Default PHY Command.
       * @see BLUETOOTH SPECIFICATION Version 5.0 | Vol 2, Part E - 7.8.49
       */
      static uint8_t create_all_phys_value(
          const phy_set_t &tx_phys,
          const phy_set_t &rx_phys
      )
      {
          /* if phy set is empty set corresponding all_phys bit to 1 */
          uint8_t all_phys = 0;
          if (tx_phys.value() == 0) {
              all_phys |= 0x01;
          }
          if (rx_phys.value() == 0) {
              all_phys |= 0x02;
          }
          return all_phys;
      }
  
  private:
      /**
       * Callback called when an event is emitted by the LE subsystem.
       */
      mbed::Callback<void(const GapEvent &)> _gap_event_cb;
  
  private:
      // Disallow copy construction and copy assignment.
      Gap(const Gap &);
  
      Gap &operator=(const Gap &);
  };
  
  } // namespace pal
  } // namespace ble
  
  #endif /* BLE_PAL_GAP_H_ */
  